lymphocyte: see blood blood, fluid pumped by the heart that circulates throughout the body via the arteries, veins, and capillaries (see circulatory system ; heart ). An adult male of average size normally has about 6 quarts (5.6 liters) of blood.
..... Click the link for more information. ; immunity immunity, ability of an organism to resist disease by identifying and destroying foreign substances or organisms. Although all animals have some immune capabilities, little is known about nonmammalian immunity.
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lymphocyte

Human lymphocyte (phase-contrast microphotograph).

(credit: Manfred Kage—Peter Arnold)

Type of leukocyte fundamental to the immune system, regulating and participating in acquired immunity. Each has receptor molecules on its surface that bind to a specific antigen. The two primary types, B cells and T cells, originate from stem cells in bone marrow and travel to lymphoid tissues. When a B cell binds to an antigen, it multiplies to form a clone of identical cells. Some of these, acted on by helper T cells, differentiate into plasma cells that produce antibodies against the antigen. Others (memory cells) multiply, providing long-term immunity to the antigen.

lymphocyte (redirected from lymphocyte-defined antigen)

lymphocyte

lymphocyte
(redirected from lymphocyte-defined antigen)